surface preparation and gaskets
Thread Starter
Burning Brakes
Joined: Jun 2006
Posts: 933
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From: St. Paul MN
surface preparation and gaskets
I'm replacing the heads on my 98. I'm now in the phase of preparing the deck surface. What tools do you guys use to do this. I don't want to damage the surface so I've been using a plastic putty knife. Do I need to get it looking like a fresh machined piece of aluminum?
Also, as I scape the old material off I notice it looks and feels almost like anti-seize lubricant. I've bought the GM MSL gaskets. Do I need to, or is it a good idea, to spray copper gasket spray on the gaskets before installing them (or is there something that GM prefers that you use)? I've always used the copper spray on my muscle cars and never had any leaking issues.
One more thing. Do the bolts enter into the water jacket? I suspect this is the case. Do I need to make sure that there is no water in the water jacket before putting in the new bolts? If so is there a better way to do this than fixing a straw to my shop vac and stuffing it down the bolt hole? Also, am I going to need to put additional sealer on the head bolts...the ones I bought appear to have sealer on them already.
Thanks!
Also, as I scape the old material off I notice it looks and feels almost like anti-seize lubricant. I've bought the GM MSL gaskets. Do I need to, or is it a good idea, to spray copper gasket spray on the gaskets before installing them (or is there something that GM prefers that you use)? I've always used the copper spray on my muscle cars and never had any leaking issues.
One more thing. Do the bolts enter into the water jacket? I suspect this is the case. Do I need to make sure that there is no water in the water jacket before putting in the new bolts? If so is there a better way to do this than fixing a straw to my shop vac and stuffing it down the bolt hole? Also, am I going to need to put additional sealer on the head bolts...the ones I bought appear to have sealer on them already.
Thanks!
Safety Car
Joined: Jul 2005
Posts: 4,275
Likes: 4
From: Vancouver WA
Get a can of permatex gasket remover. This stuff works great on cleaning the pistons too. Just be careful and cover up the area outside of the deck because this stuff is caustic. You are doing it correctly by using plastic. DO NOT USE METAL to scrap off the gasket. I also used a vacuum to suck out stuff that fell into any bolt holes, and between the pistons ring land and bore. Then I blew out the bolt holes and make sure the threads are clean. I also would turn the motor over by hand and clean the cylinder walls off with a rag and some WD 40 until there was not more carbon from the cleaning the pistons. When you clean a piston, have it at the top, and then turn the motor to pull the piston down away from the crap.
Most of the bolts are blind holes, but seams that I remember a few goes into the water jacket. I don't remember which ones.
You also can not reuse the stock OEM Head bolts. You need to get a new set, and tighten down correctly since these are tightened by stretch. (Not by a Torque setting). OR get a set of APR head botls that uses a Torque setting.
Most of the bolts are blind holes, but seams that I remember a few goes into the water jacket. I don't remember which ones.
You also can not reuse the stock OEM Head bolts. You need to get a new set, and tighten down correctly since these are tightened by stretch. (Not by a Torque setting). OR get a set of APR head botls that uses a Torque setting.
Safety Car
Joined: Sep 2003
Posts: 3,558
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From: Cape Coral FL
Michael, this article gives an in-depth procedure for exactly what you are doing. There is a lot of info about how to prep the bolt holes, deck surface, gasket types, torque sequence, etc. C5 head/cam swap.
Thread Starter
Burning Brakes
Joined: Jun 2006
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From: St. Paul MN
Looks great, I'll have to give that stuff a try!
Yeah, I've purchased new bolts, not ARP just OEM TTY bolts.
Did you use anything on your gaskets (i.e. permatex copper spray)? It certainly appears like GM used something.
Is it necessary to clean out the cylinders. I mean for sure I don't want to get any debris in the cylinders but I would imagine they will carbon back up in a matter of a few hundred miles.
Do you know if the bolts a)extend into the water jacket or b)pass through the water jacket. If they pass through the water jacket then I'll have to make sure to remove all coolant from the motor so I can evacuate all the water from the bolt holes before attempting to insert the bolts.
Yeah, I've purchased new bolts, not ARP just OEM TTY bolts.
Did you use anything on your gaskets (i.e. permatex copper spray)? It certainly appears like GM used something.
Is it necessary to clean out the cylinders. I mean for sure I don't want to get any debris in the cylinders but I would imagine they will carbon back up in a matter of a few hundred miles.
Do you know if the bolts a)extend into the water jacket or b)pass through the water jacket. If they pass through the water jacket then I'll have to make sure to remove all coolant from the motor so I can evacuate all the water from the bolt holes before attempting to insert the bolts.
Pro
Joined: Dec 2003
Posts: 651
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From: Z16 #1990 Ridgecrest CA
I just finished installing AFR 205's a few days ago on my 04 Z. I used scotch-brite sprayed with WD40 and wrapped around a small square of wood... I worked slowly and carefully to get the block clean after carefully scraping off the chunks first
Thread Starter
Burning Brakes
Joined: Jun 2006
Posts: 933
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From: St. Paul MN
Michael, this article gives an in-depth procedure for exactly what you are doing. There is a lot of info about how to prep the bolt holes, deck surface, gasket types, torque sequence, etc. C5 head/cam swap.
Thread Starter
Burning Brakes
Joined: Jun 2006
Posts: 933
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From: St. Paul MN
All holes are blind....this has me a little worried as there seems to be a lot of water coming from a few of the bolt holes. Also, the TTY bolts I purchased seem to have some rtv sealer on them (might be thread locker) which I assumed was because they pass through the water jacket...or perhaps extending into the water jacket. Are you sure that all the holes are blind? I have a 98 ls1 if that helps.
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Team Owner
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From: At the beach in little Rhody
All holes are blind....this has me a little worried as there seems to be a lot of water coming from a few of the bolt holes. Also, the TTY bolts I purchased seem to have some rtv sealer on them (might be thread locker) which I assumed was because they pass through the water jacket...or perhaps extending into the water jacket. Are you sure that all the holes are blind? I have a 98 ls1 if that helps.
Did you use MLS on 98 heads? Is it the center lower bolts that are leaking? That could be the problem.
Thread Starter
Burning Brakes
Joined: Jun 2006
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From: St. Paul MN
This is the first time the heads have been off of the motor. It might be the center lower bolts with the liquid in them. What problem are you refering to, a bad problem...like a cracked block problem?
Race Director
Joined: Oct 2002
Posts: 16,477
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From: Gone
CI 6-7-8-9-10 Veteran
St. Jude Donor '03
When you pop the heads loose, the coolant that was in them inevitably comes out, and then finds it's way into the boltholes (and in the cylinder bores too). Gravity hasn't retired quite yet...
There are things you can do to minimize that leakage prior to popping the heads, but you are past that point so...
Yes, seeing the boltholes full of coolant is very normal. Just make ABSOLUTELY SURE every bolthole is 100% dry and clean before reinstalling the heads.
Because they are blind holes, if you were to thread a tight fitting bolt down into a hole that contains liquid, you can easily create enough hydraulic pressure to crack the block.
This is one job where attention to detail and cleanliness is critical. Take your time and get every threaded hole and every mating surface as clean as you possibly can, and the job will likely be a success.
There are things you can do to minimize that leakage prior to popping the heads, but you are past that point so...Yes, seeing the boltholes full of coolant is very normal. Just make ABSOLUTELY SURE every bolthole is 100% dry and clean before reinstalling the heads.
Because they are blind holes, if you were to thread a tight fitting bolt down into a hole that contains liquid, you can easily create enough hydraulic pressure to crack the block.
This is one job where attention to detail and cleanliness is critical. Take your time and get every threaded hole and every mating surface as clean as you possibly can, and the job will likely be a success.
Thread Starter
Burning Brakes
Joined: Jun 2006
Posts: 933
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From: St. Paul MN
